Disable clickable links in Wordpress comments

I have noticed more and more links to commercial Magento extensions in the comments of my blog. That is pretty
normal, cause my Magento extensions aren't free of conflicts with other extensions and people just want to give me a
hint. But sometimes I'm not sure if they just want to ask a stupid question and make their link. SEO isn't my hot
topic. Everything I know is, good content and backlinks are important. I always visit the website of an comment and
sometimes I remove their link to an commercial Magento extension shop. But I would like to disable the links in the
comments. So I have decided to make all links in comments not clickable.

Creating a Wordpress child theme

Funny, that I call myself a PHP developer, run my Wordpress blog since 3 years I would say and never took a real
look inside. I like to use Wordpress, but I didn't like to work with it. I have found a good post about
Remove Spam Links From Wordpress Comments,
but I didn't liked the idea to write changes to the wordpress code. That's why I have decided to create a child
theme. Here is a post that describes
Child Themes in Wordpress.
Both posts together are my solution. If you already have child theme, just follow the description in the first post.
At the moment I use the twentyfifteen theme from Wordpress. I just have to create a theme directory
twentyfifteen-child with a fucntions.php and a style.css inside.